I have a 2016, 24ft Open Range Lite. The water pressure is the barely a steady stream. At home I hooked up without regulator and made no difference from using a 45psi. I traced all the lines, all hand...
I'd bet clogged screen(s) somewhere. During the manufacturing process all kinds of sawdust and such can find it's way into the water system. When you start running the water all that stuff ends up in the screen(s).